The present invention relates to a vapor assisted fuel dispensing nozzle of the general type disclosed in U.S. Pat. No. 5,832,970, the disclosure of which is herein incorporated by reference. In such a nozzle, it is sometimes desirable to provide for a shut-off valve at the tip of the nozzle spout and in the fuel supply passage to avoid drips from the spout after the nozzle is removed from the fill tube for a fuel tank of the motor vehicle. Various forms of spout tip valve systems for a fuel passage of a fuel dispensing nozzle are disclosed in U.S. Pat. Nos. 5,377,729, 5,645,116, 5,620,032, and 5,603,364. The nozzle assembly disclosed in the ""364 patent incorporates an extruded aluminum spout having a center passage or channel through which a wire extends to a valve closure cap positioned at the outer end of the spout. The inner end portion of the wire connects with an axially movable valve member which shifts downstream to an open position to allow fuel to flow and for opening the spout tip cap in response to the flow of fuel into the nozzle spout. The nozzle assembly disclosed in the ""116 patent incorporates a spring biased and fuel flow responsive valve member supported by a fitting threaded into the outer end of the fuel supply tube.
The present invention is directed to an improved vapor recovery fuel dispensing nozzle which includes a body adapted to be connected to a coaxial hose defining a fuel supply passage and a vapor return passage and a hand actuated control valve for a fuel supply passage within the body. The nozzle includes a projecting aluminum spout tube surrounding an internal plastic or metal fuel supply tube which cooperates to define an inner fuel supply passage and an outer vapor return passage around the fuel supply tube. The inner fuel supply tube extends from a spring biased poppet valve which produces a venturi suction in response to fuel flow for actuating a diaphragm mechanism which automatically closes the fuel control valve when the suction at the spout tip is blocked by fuel, in a conventional manner.
The outer spout tube receives a reinforcing stainless steel spout extension tube having peripherally spaced and axially extending vapor return grooves and a counterbore defining an internal annular valve seat for receiving a recessed tip valve member. In one embodiment, the tip valve member comprises a ball connected by a wire to a spring biased fuel pressure sensing disk slidable within a cylinder upstream of the poppet valve. When fuel is supplied to the spout assembly after the fuel valve is manually opened, the fuel pressure sensing disk is depressed against the compression spring for moving the tip valve member or ball to its open position. As soon as the fuel supply is shut off by closing of the fuel control valve, the pressure sensing disk returns to its normal position by the compression spring and moves the tip valve ball to its recessed closed position to prevent any fuel drips from the spout assembly. In another embodiment, the tip valve member is guided between its open a d closed positions by a cage recessed within the counterbore and an outwardly projecting valve stem surrounded by a compression spring.
Other features and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.